--- key: lesson/choice-cost type: lesson id: choice-cost lang: en title: Choice costs and situational value summary: >- Compare options through time, resources and context to uncover a dominant choice. updatedAt: '2026-10-20' status: active url: 'https://gamemechanics.pro/en/lessons/choice-cost/' jsonUrl: 'https://gamemechanics.pro/api/v1/knowledge/en/lesson/choice-cost.json' markdownUrl: 'https://gamemechanics.pro/content/knowledge/en/lesson/choice-cost.md' aliases: - экономика - economy - баланс tags: - balance - choices - economy sourceIds: - source-2d559b13bf74d659 sources: - id: source-2d559b13bf74d659 title: 'Ian Schreiber: Level 3, Transitive Mechanics and Cost Curves' url: >- https://gamebalanceconcepts.wordpress.com/2010/07/21/level-3-transitive-mechanics-and-cost-curves/ verifiedAt: null relations: - type: requires direction: outgoing label: Before you start key: lesson/scope-and-prototype title: Scope and a testable prototype url: 'https://gamemechanics.pro/en/lessons/scope-and-prototype/' jsonUrl: >- https://gamemechanics.pro/api/v1/knowledge/en/lesson/scope-and-prototype.json markdownUrl: >- https://gamemechanics.pro/content/knowledge/en/lesson/scope-and-prototype.md - type: requires direction: incoming label: Continue learning key: lesson/controlled-randomness title: Randomness and unlucky streaks url: 'https://gamemechanics.pro/en/lessons/controlled-randomness/' jsonUrl: >- https://gamemechanics.pro/api/v1/knowledge/en/lesson/controlled-randomness.json markdownUrl: >- https://gamemechanics.pro/content/knowledge/en/lesson/controlled-randomness.md - type: requires direction: incoming label: Continue learning key: lesson/progression-pacing title: 'Progression: capabilities and pacing' url: 'https://gamemechanics.pro/en/lessons/progression-pacing/' jsonUrl: >- https://gamemechanics.pro/api/v1/knowledge/en/lesson/progression-pacing.json markdownUrl: >- https://gamemechanics.pro/content/knowledge/en/lesson/progression-pacing.md - type: explains direction: outgoing label: Apply the principle key: mechanic/rpg-grind--item-evolution title: Item evolution url: 'https://gamemechanics.pro/en/knowledge/mechanic/rpg-grind--item-evolution/' jsonUrl: >- https://gamemechanics.pro/api/v1/knowledge/en/mechanic/rpg-grind--item-evolution.json markdownUrl: >- https://gamemechanics.pro/content/knowledge/en/mechanic/rpg-grind--item-evolution.md - type: practices direction: outgoing label: Put it into practice key: practice/last-ferry title: The last ferry url: 'https://gamemechanics.pro/en/knowledge/practice/last-ferry/' jsonUrl: 'https://gamemechanics.pro/api/v1/knowledge/en/practice/last-ferry.json' markdownUrl: 'https://gamemechanics.pro/content/knowledge/en/practice/last-ferry.md' - type: reviews direction: outgoing label: Review through a lens key: lens/schell-039 title: Meaningful Choices url: 'https://gamemechanics.pro/en/knowledge/lens/schell-039/' jsonUrl: 'https://gamemechanics.pro/api/v1/knowledge/en/lens/schell-039.json' markdownUrl: 'https://gamemechanics.pro/content/knowledge/en/lens/schell-039.md' - type: contains direction: incoming label: Learning paths key: path/balance title: Balance and progression url: 'https://gamemechanics.pro/en/learn/balance/' jsonUrl: 'https://gamemechanics.pro/api/v1/knowledge/en/path/balance.json' markdownUrl: 'https://gamemechanics.pro/content/knowledge/en/path/balance.md' placements: [] supersededBy: [] attributes: category: design level: beginner minutes: 5 endsAt: null provenance: >- Original gamemechanics.pro material. Check illustrative examples in your own project. license: CC-BY-4.0 codeLicense: MIT attribution: gamemechanics.pro contributors --- # Choice costs and situational value id: choice-cost type: lesson key: lesson/choice-cost lang: en status: active url: https://gamemechanics.pro/en/lessons/choice-cost/ Compare options through time, resources and context to uncover a dominant choice. ## Prerequisites Two weapons with different numbers may offer the same decision: take the one that is better in every situation. Begin balancing by asking what the player pays and when they receive value. ## The principle Cost can include resources, time, an occupied slot and a forgone opportunity. Comparison through a common cost model, as in [Ian Schreiber's lecture](https://gamebalanceconcepts.wordpress.com/2010/07/21/level-3-transitive-mechanics-and-cost-curves/), helps identify a suspicious option. A single ratio cannot describe all gameplay value. An option dominates another in the selected model if it is no worse on every relevant criterion and better on at least one. “Relevant” requires explicit assumptions: range or accuracy cannot silently disappear from a real game's comparison. ## Practical example ### Rescue tools In an illustrative game, players cut through debris. A saw removes 12 durability per action and consumes 3 charges. A cutter removes 8 and consumes 2. Both remove 4 durability per charge. That does not establish equivalence. For debris with 8 durability, the cutter finishes in one action and 2 charges, while the saw needs one action and 3. For debris with 12 durability, the saw needs one action and 3 charges; the cutter needs two actions and 4. Rounding action counts changes the preferred option. This model has no misses, energy recovery or damage to the rescuer; revisit it when adding those systems. List situations before changing numbers. To give the saw a role, test different debris durability and time limits. Do not invent cutter immunity merely to justify its neighbor: first ask whether a second tool is needed. ## Common mistakes - Comparing only damage per second when scarce charges determine the decision. - Equalizing averages while ignoring rounding and thresholds. - Making every option equal in every situation and removing the reason to choose. ## Verify it - Compute action count by rounding durability divided by tool strength upward. - Record actions, charge consumption and the reason for preference in three situations. - Find a justified use for every option you intend to keep. - Check the model in play: waiting for animation may also be a cost. ## Prompt for an AI agent > Make a table for debris with durability 8, 12 and 20. Count actions and charges separately and state assumptions. Propose one change if a tool is never useful. Do not claim the table proves balance. Continue with [Last Ferry](/en/practice/#last-ferry) and the [Meaningful Choices lens](/en/lenses/#schell-039). ## Connected materials - Before you start: [Scope and a testable prototype](https://gamemechanics.pro/en/lessons/scope-and-prototype/) (key: lesson/scope-and-prototype) - Continue learning: [Randomness and unlucky streaks](https://gamemechanics.pro/en/lessons/controlled-randomness/) (key: lesson/controlled-randomness) - Continue learning: [Progression: capabilities and pacing](https://gamemechanics.pro/en/lessons/progression-pacing/) (key: lesson/progression-pacing) - Apply the principle: [Item evolution](https://gamemechanics.pro/en/knowledge/mechanic/rpg-grind--item-evolution/) (key: mechanic/rpg-grind--item-evolution) - Put it into practice: [The last ferry](https://gamemechanics.pro/en/knowledge/practice/last-ferry/) (key: practice/last-ferry) - Review through a lens: [Meaningful Choices](https://gamemechanics.pro/en/knowledge/lens/schell-039/) (key: lens/schell-039) - Learning paths: [Balance and progression](https://gamemechanics.pro/en/learn/balance/) (key: path/balance) ## Sources and provenance Original gamemechanics.pro material. Check illustrative examples in your own project. - [Ian Schreiber: Level 3, Transitive Mechanics and Cost Curves](https://gamebalanceconcepts.wordpress.com/2010/07/21/level-3-transitive-mechanics-and-cost-curves/) (id: source-2d559b13bf74d659) CC-BY-4.0 · gamemechanics.pro contributors